The invention relates to a cushioning assembly for a chair, couch, bed, etc., wherein springs are mounted on a support (foundation), and a pad is laid upon the springs.
Steel springs are often used for cushioning, by being arranged within a pad, the spring-containing pad resting upon a support (e.g., slats). Arranged in regular patterns in the form of spring cores between layers of cushion, the steel springs absorb the forces generated by a user sitting or lying on the pad and adapt to the shape of the body, i.e., the pad is deformed in such a manner that it adapts to the shape of the body in accordance with the distribution of force generated by the position of the user. It is also known to mount the more or less elastic pad on slats, which in turn are mounted in flexible mountings arranged on both sides, and are designed either as rigid solid slats or as flexible laminated wood slats. Thus, the desired and necessary flexibility and adaptability are guaranteed.
Since the steel springs make noise over the course of time in the cushion units, and since the steel springs can break, whereby the tips of the broken springs can penetrate the pad cover and thus disturb a peaceful repose, an attempt has already been made to sew the steel springs individually into sleeves made of material. However, the metal of the springs is attacked by the unavoidable moisture, a condition that can result in the spring breaking following corrosion.
In the case of a slatted base as the foundation, the risk of corrosion can be ruled out through the use of elastic buffers as holding elements in order to support on both sides the rigid or springy slats (EU-A-0 031 132) and the development of noise can be largely suppressed. Even the force that is necessary to deform each slat to a specific degree can be adjusted through a specific design of the cross slats, but no force gradation can be achieved across the width of the slats, especially since here an influence induced by existing moisture cannot be excluded.
To achieve such a gradation of the force, it has already been proposed (EP-A-0 401 712) that the entire surface of the foundation be covered with elastic elements that are positioned in U-profiles in order to avoid an overloading and to limit the available spring excursion. For this surface layering for furniture intended for lying or sitting, such as beds or the like, the support surface for a loose cushion such as a mattress (as already known from DE 36 12 603 A1) is divided into subareas, which are arranged in regular patterns, and each individual spring element of which is designed flexibly. In so doing, the spring elements are affixed to slats, e.g., slats of U-shaped cross section, or trough-shaped slats, which run parallel to the longitudinal bars of the frame. There is provided a suitable mounting mechanism, so that the spring elements can be fixed in position. The free end of these spring elements, i.e., the head, is provided with a supporting plate, which is attached to the head of the spring. The plates limit the extent of spring compression by engaging vertical flanges of the U profiles of the slats in order to preserve the spring elements. However, limiting the extent of spring compression prevents the reclining area from fully adapting to the shape of the reclining body of a human. Also, the mounting of the spring elements on the carrying slats and providing the spring elements with the supporting plates are necessary manufacturing steps that have to be performed manually, and their cost renders the manufacture of such a foundation expensive.
Those are the problems on which the invention is based and according to which a cushion assembly of the aforementioned kind with springs as the foundation is to be improved in such a manner that a cushion assembly having only slightly elastic mattress-like pads can be assembled in a simple manner. The springs are identical and simple to produce and have different, preferably progressive, spring characteristics, by means of which the spring excursion can also be limited for expectant loads. Owing to the simple construction, adaptability of the cushion assembly to varying peculiarities is possible, whereby external influences, such as moisture and the like, are to be ruled out, and wherein the spring characteristics shall also be variable.